If the numbers 1 to 10 are all multiplied together, how many zeros are at the end of the answer?
The numbers 72, 8, 24, 10, 5, 45, 36, 15 are grouped in pairs so that each pair has the same product. Which number is paired with 10?
The following sequence continues indefinitely... Which of these integers is a multiple of 81?
If $n$ is a positive integer, how many different values for the remainder are obtained when $n^2$ is divided by $n+4$?
How many pairs of numbers of the form x, 2x+1 are there in which both numbers are prime numbers less than 100?
Our school dinners offer the same choice each day, and each day I try a new option. How long will it be before I eat the same meal again?
How many of the numbers 1 to 20 are not the sum of two primes?
How many zeros does 50! have at the end?
At a cinema a child's ticket costs £$4.20$ and an adult's ticket costs £$7.70$. How much did is cost this group of adults and children to see a film?
Flora has roses in three colours. What is the greatest number of identical bunches she can make, using all the flowers?
Can you find three primes such that their product is exactly five times their sum? Do you think you have found all possibilities?
Using the hcf and lcf of the numerators, can you deduce which of these fractions are square numbers?
Can you form this 2010-digit number...
Find out which two distinct primes less than $7$ will give the largest highest common factor of these two expressions.
Tina has chosen a number and has noticed something about its factors. What number could she have chosen? Are there multiple possibilities?
Two numbers can be placed adjacent if one of them divides the other. Using only $1,...,10$, can you write the longest such list?
Roo wants to puts stickers on the cuboid he has made from little cubes. Will he have any stickers left over?
Will this product give a perfect square?
Each time a class lines up in different sized groups, a different number of people are left over. How large can the class be?
Weekly Problem 5 - 2014
Weekly Problem 15 - 2014
Weekly Problem 26 - 2014
Weekly Problem 28 - 2014
Weekly Problem 39 - 2014
Weekly Problem 1 - 2015
Weekly Problem 4 - 2015
What is the last-but-one digit of 99! ?
How many tables of each type does Mark need at his birthday party?
How many times has Simon's age changed from a square to a prime?
What is the smallest number of pieces grandma should cut her cake into to guarentee each grandchild gets the same amount of cake and none is left over.
The year 2010 is one in which the sum of the digits is a factor of the year itself. What is the next year that has the same property?
A list is made of every digit that is the units digit of at least one prime number. How many digits appear in the list?
Last week, Tom and Sophie bought some stamps for their collections. Each stamp Tom bought cost him £1.10, whilst Sophie paid 70p for each of her stamps. Between them they spent exactly £10. How many stamps did they buy in total?
What percentage of the integers between 1 and 10,000 are square numbers?
To power should 4^4 be raised to give 8^8?